The invention disclosed and claimed herein generally pertains to head apparatus which is mountable upon the spindlehead of a machine tool or machining center, and which enables a cutting tool to be transversely fed or outwardly fed at a closely controlled feedrate. More particularly, the invention pertains to apparatus of the above type which is attachable to and detachable from a machine spindlehead which is capable of driving a number of different tools. Even more particularly, the invention pertains to apparatus of the above type which may be stored in a tool storage facility of a machining center, and which may be routinely transferred between the tool storage facility and a machine spindlehead by means of a conventional automatic tool changing system.
In order to operate certain types of spindle driven cutting tools, it is necessary to reciprocate an actuating element contained in the tool, as the tool is rotated by the spindle. As the actuating element is moved, the cutting element of the tool is moved transversely to the spindle axis (cross fed) or is moved along the spindle axis (outwardly fed). Examples of tools which are operated in such manner include grooving tools, cross-feed facing tools, and feed-out boring tools.
Techniques and structure for operating the above types of tools are, of course, well known in the art. In some techniques, an attachment upon which the tool is mounted is placed upon the spindle and a mechanism within the attachment is driven by the spindle to feed the tool. In other techniques, a draw rod is provided which coaxially traverses the spindle, and engages and reciprocates the actuating element of a cutting tool. However, if some of such tool feeding techniques are employed, certain disadvantages or limitations may be encountered. For example, if the spindlehead of a machine is adapted to drive feedable tools in accordance with certain prior art techniques, it may be unable to drive tools which require only rotary motion. A number of manual tasks may have to be performed to adapt the machine to operate nonfeedable tools, whereby machine flexibility is significantly reduced.
The present invention provides a feeding head for a machine tool or machining center which is capable of controllably driving both cross-feed and feed-out tools. The feeding head may be readily attached to and detached from a driving spindle by means of a conventional automatic tool changing system, whereby the driving spindle may be rapidly adapted to operate both feedable and non-feedable tools. The rate at which the feeding head feeds a tool may be closely controlled, yet is completely independent of the revolution rate of the driving spindle.